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arXiv · 1609.02820

Do nuclear collisions create a locally equilibrated quark-gluon plasma?

Paul Romatschke
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Abstract

Experimental results on azimuthal correlations in high energy nuclear collisions (nucleus-nucleus, proton-nucleus and proton-proton) seem to be well described by viscous hydrodynamics. It is often argued that this agreement implies either local thermal equilibrium or at least local isotropy. In this note, I present arguments why this is not the case. Neither local near-equilibrium nor near-isotropy are required in order for hydrodynamics to offer a successful and accurate description of experimental results. However, I predict the breakdown of hydrodynamics at momenta of order seven times the temperature, corresponding to a smallest possible QCD liquid drop size of 0.15 fm.

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Paul Romatschke. 2017-01-17. Do nuclear collisions create a locally equilibrated quark-gluon plasma?. https://doi.org/10.1140/epjc%2Fs10052-016-4567-x

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